Kompozitni materijali su, od svog uvođenja u stomatološku praksu, doživeli brojne modifikacije, ali i dalje postoji značajan prostor za njihovo
unapređenje. Bulk-fill kompoziti predstavljaju grupu savremenih kompozitnih materijala namenjenih za restauraciju bočnih zuba u slojevima debljine
od 4 do 5 mm, čime se smanjuje potreba za slojevitim apliciranjem materijala u dublje kavitete. Njihov razvoj proistekao je iz potrebe da se
restaurativna procedura pojednostavi, a kliničko vreme rada sa pacijentima skrati.
Polimerizaciona kontrakcija i neusklađen koeficijent termičke ekspanzije u odnosu na zubna tkiva predstavljaju glavne uzroke nastanka rezidualnih
napona na spoju ispun-zub, gubitka marginalnog integriteta, pojave mikropukotina, postoperativne preosetljivosti, kao i marginalne prebojenosti ili
sekundarnog karijesa u kasnijim fazama. Polimerizaciona kontrakcija kod bulk-fill kompozita iznosi između 1–2%, što je nešto niže u poređenju sa
univerzalnim kompozitima, dok kontrakcioni napon dostiže vrednosti od 1,7 do 2,4 MPa. Stepen konverzije u kliničkim uslovima kreće se između 50% i
70%, pri čemu oko 10% ostaje u vidu neizreagovanih monomera koji se mogu oslobađati u pljuvačku ili dentinski likvor, potencijalno negativno utičući
na pulpno tkivo. Efikasna polimerizacija zavisi od intenziteta svetlosti i njene prodornosti u dublje slojeve materijala. Visokoreaktivni fotoinicijatori,
poput Ivocerina, u kombinaciji sa povećanom translucencijom, omogućavaju bolju prohodnost svetlosti i bržu polimerizaciju, iako uz blago
kompromitovane estetske osobine. Inovacije kao što su modifikovani monomeri (npr. ekspandirajući monomeri), povećan sadržaj punilaca i dodatak
staklenih vlakana, doprinose smanjenju kontrakcionog napona i poboljšanju marginalnog integriteta. Povećana gustina umrežavanja u strukturi ovih
materijala rezultira većom tvrdoćom, boljom otpornošću na habanje i dugoročnom stabilnošću, što ukupno doprinosi superiornim mehaničkim
osobinama.
Uz pravilnu kliničku primenu, bulk-fill kompoziti omogućavaju značajno unapređenje efikasnosti u svakodnevnoj stomatološkoj praksi, bez ugrožavanja
kvaliteta restauracije, mehaničkih svojstava i marginalne adaptacije u poređenju sa univerzalnim kompozitima.
Ključne reči: Bulk-fill kompoziti, polimerizaciona kontrakcija, stepen konverzije, marginalna adaptacija

Bruxism is a parafunctional activity of the masticatory system, which is characterized by clenching or scraping of teeth. This condition is often accompanied by a change in the shape and size of the teeth, as well as the function of the stomatognathic system. Bruxism can occur during sleep and in the waking state. The etiology is multifactorial and all causes can be divided into peripheral and central. The clinical signs and symptoms of bruxism are primarily characterized by temporomandibular disorders, the appearance of bruxofacets and changes in the hard dental tissues, supporting apparatus of the teeth and masticatory muscles, as well as headaches. The diagnosis of bruxism is made on the basis of anamnesis and clinical signs and symptoms, while electromyography and polysomnographic analysis are used in scientific researches. Therapy is aimed at controlling etiological factors and reducing symptoms. Occlusal splints are the most commonly used in the treatment of bruxism. Medications are used in situations when other methods, including psychotherapy, do not give positive results. Given the multifactorial etiology, the therapeutic approach must be multidisciplinary. The approach to the patient must be individual in order to treat as effectively as possible.

Introduction: Direct and indirect pulp capping is a therapeutic procedure to preserve the tooth's vitality. The aim was to scan electron and polarization microscopy: analyze changes in cellular and extracellular components of dental pulp after direct and indirect overlay with glass-ionomer cement (GIC), determine the appearance of the dentine surface after direct and indirect pulping overlap with GIC and forms a proposal for a clinical application of preparations if it provides good and effective dentingenesis. Methods: The experiment was performed on experimental animals (domestic swine). For this research, alkaline cement was used ALFAGAL* bejz. On the teeth of the experimental group, preparations of the V class were made from the vestibular side. Twenty-two teeth were made indirectly, and twenty –two teeth directly covered with pulp. After completion of the preparation, dentin is directly covered with glass-ionomer cement (GIC) Alfagal* bejz. Through the ALFAGAL material for definitively closing cavities (amalgam) is laid. On the teeth where the perforation of the pulp chamber was made, ALFAGAL bejz was loaded directly into the pulp chamber, and through this the cavity was definitely sealed with GIC FUJI IX (GC Japan). Suitably prepared teeth and pulp were observed by SEM and a polarization microscope. Results: By observing and analyzing the obtained results, on a polarization and scanning electron microscope compared to the control group, results were obtained which can have a significant clinical implication in the biological treatment of the pulp. Alfagalbejz is directly applied in the pulp chamber: the boundary between newly developed reparative dentine is detected in the normal dentine structure, amorphous dentine, reproduction of connective tissue cells without pro inflammatory reactions and initial dedifferentiation in odontoblast, young blood vessels and cells (fibrocytes, histiocytes and fibroblasts) are observed. Indirectly applied Alfagal* bejz indicates the presence of different maturation stages of dentin, dentinal canals are clearly visible with a normal dentin structure, zero amorphous dentine and immature dentine structure are observed as well. The presence of an amorphous calcite of the dentine structure indicates the initial creation of a solid tissue barrier, which is the goal of the experiment. Conclusion: The results obtained by experimental research suggest ALFAGAL bejz as a good material for the direct and indirect overlap of the pulp.

When pulp tissue gets exposed, therapy procedures are supposed to promote healing and to ease forming of reparative dentin in order to preserve vitality and health of the pulp. Vital pulp therapy (VPT) procedure includes removal of the local irritants as well as application of protective materials directly or indirectly on tooth pulp. Vital pulp therapy may be used for the treatment of the reversible pulp diseases in order to promote root development and to form apical region which will ensure correct endodontic tooth treatment in later stages. There are numerous controversies concerning vital pulp therapy but mostly related to the choice of the materials, correct technique and evaluation of the final therapy results. The goal of the experimental research is to use scanning electron and polarized microscopy to analyze modifications on cellular and extracellular components of the tooth pulp after direct and indirect overlaying with materials on the calcium hydroxide basis (Calcimol VOCO USA). We will also determine the appearance of dental surface after direct and indirect overlaying and if Calcimol proves good and effective in dentinogenesis, we will propose it for clinical usage. Research has been conducted on experimental animals (pig). Materials used in this research were on calcium hydroxide - base, Calcimol. V class preparation has been applied on the teeth of the experimental group. Eleven teeth have been overlaids directly and the same number of teeth has been overlaid indirectly. After the preparation, materials based on calcium hydroxide have been applied and cavity has been closed with materials from the glass ionomer cement group (FUJI IX GC Japan). Teeth that were treated with pulp perforation had their chambers filled with materials on calcium hydroxide-base and their cavities were closed with glass ionomer cement (FUJI IX GC Japan). Correctly prepared teeth have been observed with SEM and polarization microscopes. Observing and analyzing of the results with polarization and scanning electron microscope in comparison with control group showed that gained results may have significant clinical implication in biological pulp treatment. Directly applied Calcimol observed through polarization microscope points to intensive changes in blood vessels and beginnings of erythrocyte disintegration, distinct extravasation, and appearance of the small necrotic spots. SEM analyzes shows contact of the amalgam-Calcimol without new amorphous dentinal structures. Indirectly applied Calcimol observed through polarization microscope points to newly formed dentinal structures, calcification cores surrounded by huge cells and blood vessels presence. SEM analyzes shows clear border between newly formed dentinal tubules and ordinary dentinal structure. Gained results suggest application of the Calcimol as a material for indirect pulp overlay while its application in indirect overlay isn’t indicated.